What fraction of a clockwise revolution does the hour hand of a clock turn through, when it goes from
(a) 3 to 9
(b) 4 to 7
(c) 7 to 10
(d) 12 to 9
(e) 1 to 10
(f) 6 to 3

Solution:

We will use the concept of fractions to solve this.

To find the portion of the clock swept by the hour hand between any two numbers(hours) say 'a' and 'b'  where b > a will be found by subtracting 'a' from 'b' i.e, b - a.

Also, to find the fraction of a clockwise revolution between 'a' and 'b' we now divide the portion of the clock swept by the hour hand between them by 12 (since, the clock is divided into 12 equal divisions)

Hence, the fraction will be (b - a) / 12

Using this concept, let's solve the given problems.

(a) 3 to 9

Lets first subtract 3 from 9 and then divide the answer by 12

9 – 3 = 6 ÷ 12 = 1/2 of a clockwise revolution

(b) 4 to 7

Lets first subtract 4 from 7 and then divide the answer by 12

7 – 4 = 3 ÷ 12 = 1/4 of a clockwise revolution

(c) 7 to 10

Lets first subtract 7 from 10 and then divide the answer by 12

10 – 7 = 3 ÷ 12 = 1/4 of a clockwise revolution

(d) 12 to 9 i.e., 0 to 9 [Since, 12 is at 0^th position of the clock]

Lets first subtract 0 from 9 and then divide the answer by 12

9 – 0 = 9 ÷ 12 = 3/4 of a clockwise revolution

(e) 1 to 10

Lets first subtract 1 from 10 and then divide the answer by 12

10 – 1 = 9 ÷ 12 = 3/4 of a clockwise revolution

(f) 6 to 3 i.e., 6 to 12 and then 12 to 3

6 to 12 = 12 – 6 = 6 and 12 to 3 = 0 to 3 = 3 – 0 = 3

6 + 3 = 9 ÷ 12 = 3/4 of a clockwise revolution

---

Class 6 Maths NCERT Solutions Chapter 5 Exercise 5.2 Question 1

What fraction of a clockwise revolution does the hour hand of a clock turn through, when it goes from (a) 3 to 9 (b) 4 to 7 (c) 7 to 10 (d) 12 to 9 (e) 1 to 10 (f) 6 to 3

Summary:

The fraction of a clockwise revolution the hour hand of a clock turns through, when it goes from (a) 3 to 9 (b) 4 to 7 (c) 7 to 10 (d) 12 to 9 (e) 1 to 10 (f) 6 to 3 are (a) 1/2 (b) 1/4 (c) 1/4 (d) 3/4 (e) 3/4 (f) 3/4

---

☛ Related Questions:

• Where Will The Hand Of A Clock Stop If It A Starts At 12 And Makes 1 2 Of A Revolution Clockwise B Starts At 2 And Makes 1 2 Of A Revolution Clockwise C Starts At 5 And Makes
• Which Direction Will You Face If You Start Facing A East And Make 1 2 Of A Revolution Clockwise Z B East And Make 1 1 2 Of A Revolution Clockwise Z C West And Make 3 4
• What Part Of A Revolution Have You Turned Through If You Stand Facing A East And Turn Clockwise To Face North B South And Turn Clockwise To Face East C West And Turn
• Find The Number Of Right Angles Turned Through By The Hour Hand Of A Clock When It Goes From A3 To 6 B 2 To 8 C 5 To 11 D 10 To 1 E 12 To 9 F 12 To 6